Method for determining transport block size and signal transmission method using the same

ABSTRACT

A method and device for segmenting, CRC encoding and turbo encoding a CRC attached transport block.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a Continuation of co-pending application Ser. No. 12/332,165 filed on Dec. 10, 2008, which claims priority to Korean Patent Application 10-2008-0097705, filed on Oct. 6, 2008, U.S. Provisional Application 61/024,914 filed on Jan. 31, 2008 and U.S. Provisional Application 61/026,143 filed on Feb. 5, 2008. The entire contents of all of the above applications are hereby incorporated by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a method and device for effectively determining the size of a data block or a transport block in a wireless communication system, and a method for transmitting signals using the same method.

2. Discussion of the Background Art

Generally, in a communication system, a transmission end of the communication system encodes transmission information using a forward error correction code, and transmits the encoded information to a reception end of the communication system, such that errors caused by a channel can be corrected in the information received in the reception end. The reception end demodulates a reception signal, decodes a forward error correction code, and recovers the transmission information transferred from the transmission end. During this decoding process, reception signal errors caused by a channel can be corrected.

There are various kinds of forward error correction codes that may be used. For the convenience of description, a turbo code will hereinafter be described as an example of the forward error correction code. The turbo code includes a recursive systematic convolution encoder and an interleaver. In case of actually implementing the turbo code, the interleaver facilitates parallel decoding, and an example of this interleaver may be a quadratic polynomial permutation (QPP) interleaver. It is well known in the art that this QPP interleaver maintains a superior throughput or performance in only a specific-sized data block. In this case, the term “data block” is block unit data encoded by the encoder. If we think block unit data transferred from an upper layer to a physical layer is encoded without segmentation discussed below, this data block may also be called as a transport block (TB). On the other hand, if we think the segmentation of the transport block to be encoded, this data block may be matched to “a code block”.

In general, the larger the data-block size, the higher the turbo-code performance. A data block of more than a specific size is segmented into a plurality of small-sized data blocks by an actual communication system, such that the small-sized data blocks are encoded for the convenience of actual implementation. The divided small-sized data blocks are called code blocks. Generally, although these code blocks have the same size, one of several code blocks may have another size due to the limitation of the QPP interleaver size. A forward error correction coding process on the basis of a code block of a predetermined interleaver size is performed on the small-sized data blocks, and the resultant data blocks are then transferred to an RF (Radio Frequency) channel. In this case, a burst error may occur in the above process of transferring the resultant data blocks to the RF channel, such that the above resultant data blocks are interleaved to reduce an influence of the burst error. The interleaved data blocks are mapped to actual radio resources, such that the mapped result is transferred.

An amount of radio resources used in an actual transmission process is constant, such that a rate matching process should be performed on the encoded code blocks due to the constant amount of radio resources. Generally, the rate matching process is implemented by a puncturing or a repetition. For example, the rate matching may also be performed on the basis of an encoded code block in the same manner as in a WCDMA of the 3GPP. For another example, a systematic part and a parity part of the encoded code block may be separated from each other. The rate matching process may be performed on the systematic part and the parity part together. On the other hand, the rate matching process may also be independently performed on each of the systematic part and the parity part.

FIG. 1 is a conceptual diagram illustrating basic operations of a turbo encoder.

As shown in FIG. 1, if a turbo-encoder receives one code block, it divides the received one code block into a systematic part (S) and parity parts (P1 and P2). The systematic part S and the parity parts P1 and P2 pass through individual sub-block interleavers, respectively. Thus, the systematic part S and the parity parts P1 and P2 may be interleaved by different sub-block interleavers, and the interleaved result is stored in a circular buffer.

As can be seen from FIG. 1, the systematic part and the parity parts of the code block may be separated from each other, and the rate matching process is performed on the individual separated parts, but the example of FIG. 1 has been disclosed for only illustrative purposes and the scope and spirit of the present invention are not limited to this example and can also be applied to other examples. For the convenience of description, it is assumed that a code rate is a value of ⅓.

Although a variety of transport block sizes may be defined according to service categories of an upper layer, it is preferable that the transport block sizes may be quantized to effectively perform the signaling of various transport block sizes. During the quantization process, in order to adjust a source data block transferred from an upper layer to the size of a data block of a physical layer, a dummy bit is added to the source data block. During this quantization process, it is preferable to minimize the amount of added dummy bits.

SUMMARY OF THE INVENTION

To achieve these objects and other advantages and in accordance with the purpose of the invention, as embodied and broadly described herein, a signal transmission method and device is presented, the method comprising: determining the number of code blocks to be used for transmitting a transport block with a specific size, and mapping the transport block to the code blocks corresponding to the determined number; attaching a cyclic redundancy check (CRC) to each of the code blocks; encoding each of the CRC-attached code blocks by a turbo-encoder including an internal interleaver; and transmitting the encoded code blocks, wherein the specific size of the transport block corresponds to any transport block size in predetermined transport block size combinations, and wherein any transport block size in the predetermined transport block size combinations is predetermined such that the sum of a length of any one code block from among the code blocks mapped to the transport block with the specific length and a length of the CRC attached to the one code block is equal to a block size of the internal interleaver.

The block size of the internal interleaver of the turbo-encoder may be predetermined as a combination of predetermined bit lengths.

Under the above-mentioned assumption, if the number of code blocks to be used for transmitting the transport block is 1, the specific transport block size may be any one of the predetermined transport block size combinations in which any one of the predetermined transport block size corresponds to the sum of a CRC length and the predetermined internal interleaver's block sizes.

Under the same assumption, if the number of code blocks to be used for transmitting the transport block is at least 2, the transport block is segmented into at least two code blocks having the same length, and is mapped to the at least two code blocks.

The above-mentioned operations may be generalized as the following expression.

If the specific size of the transport block is N, the number of the code blocks to be used for transmitting the transport block is M, the length of each of the M code blocks is N_(c), and the length of the CRC is L, the specific transport block size N may satisfy an equation denoted by N=M*N_(c)−L, and the specific transport block size may correspond to any one of the predetermined transport block size combinations in which a value of Nc+L corresponds to the internal interleaver's block sizes predetermined as a combination of predetermined bit lengths.

In more detail, the block size of the internal interleaver of the turbo-encoder may predetermined as ‘K’ value according to an index (i) in a following Table 1:

TABLE 1 i K 1 40 2 48 3 56 4 64 5 72 6 80 7 88 8 96 9 104 10 112 11 120 12 128 13 136 14 144 15 152 16 160 17 168 18 176 19 184 20 192 21 200 22 208 23 216 24 224 25 232 26 240 27 248 28 256 29 264 30 272 31 280 32 288 33 296 34 304 35 312 36 320 37 328 38 336 39 344 40 352 41 360 42 368 43 376 44 384 45 392 46 400 47 408 48 416 49 424 50 432 51 440 52 448 53 456 54 464 55 472 56 480 57 488 58 496 59 504 60 512 61 528 62 544 63 560 64 576 65 592 66 608 67 624 68 640 69 656 70 672 71 688 72 704 73 720 74 736 75 752 76 768 77 784 78 800 79 816 80 832 81 848 82 864 83 880 84 896 85 912 86 928 87 944 88 960 89 976 90 992 91 1008 92 1024 93 1056 94 1088 95 1120 96 1152 97 1184 98 1216 99 1248 100 1280 101 1312 102 1344 103 1376 104 1408 105 1440 106 1472 107 1504 108 1536 109 1568 110 1600 111 1632 112 1664 113 1696 114 1728 115 1760 116 1792 117 1824 118 1856 119 1888 120 1920 121 1952 122 1984 123 2016 124 2048 125 2112 126 2176 127 2240 128 2304 129 2368 130 2432 131 2496 132 2560 133 2624 134 2688 135 2752 136 2816 137 2880 138 2944 139 3008 140 3072 141 3136 142 3200 143 3264 144 3328 145 3392 146 3456 147 3520 148 3584 149 3648 150 3712 151 3776 152 3840 153 3904 154 3968 155 4032 156 4096 157 4160 158 4224 159 4288 160 4352 161 4416 162 4480 163 4544 164 4608 165 4672 166 4736 167 4800 168 4864 169 4928 170 4992 171 5056 172 5120 173 5184 174 5248 175 5312 176 5376 177 5440 178 5504 179 5568 180 5632 181 5696 182 5760 183 5824 184 5888 185 5952 186 6016 187 6080 188 6144

Under the above-mentioned assumption, if the number of code blocks to be used for transmitting the transport block is 1, the specific transport block size may be any one of the transport block size combinations in which any transport block size corresponds to the sum of a K value shown in Table 1 and a CRC length.

The above-mentioned operations may be generalized as the following expression.

If the specific size of the transport block is N, the number of the code blocks to be used for transmitting the transport block is M, the length of each of the M code blocks is N_(c), and the length of the CRC is L, the specific transport block size N may satisfy an equation denoted by N=M*N_(c)−L, and the specific transport block size may correspond to any one of transport block size combinations in which a value of Nc+L corresponds to the K value shown in the above table 1.

The specific size N of the transport block may be set to a length selected from among combinations shown in a following table 2 according to the number M of the code blocks to be used for transmitting the transport block.

TABLE 2 M N 2 6200 2 6328 2 6456 2 6584 2 6712 2 6840 2 6968 2 7096 2 7224 2 7352 2 7480 2 7608 2 7736 2 7864 2 7992 2 8120 2 8248 2 8376 2 8504 2 8632 2 8760 2 8888 2 9016 2 9144 2 9272 2 9400 2 9528 2 9656 2 9784 2 9912 2 10040 2 10168 2 10296 2 10424 2 10552 2 10680 2 10808 2 10936 2 11064 2 11192 2 11320 2 11448 2 11576 2 11704 2 11832 2 11960 2 12088 2 12216 3 12384 3 12576 3 12768 3 12960 3 13152 3 13344 3 13536 3 13728 3 13920 3 14112 3 14304 3 14496 3 14688 3 14880 3 15072 3 15264 3 15456 3 15648 3 15840 3 16032 3 16224 3 16416 3 16608 3 16800 3 16992 3 17184 3 17376 3 17568 3 17760 3 17952 3 18144 3 18336 4 18568 4 18824 4 19080 4 19336 4 19592 4 19848 4 20104 4 20360 4 20616 4 20872 4 21128 4 21384 4 21640 4 21896 4 22152 4 22408 4 22664 4 22920 4 23176 4 23432 4 23688 4 23944 4 24200 4 24456 5 24496 5 24816 5 25136 5 25456 5 25776 5 26096 5 26416 5 26736 5 27056 5 27376 5 27696 5 28016 5 28336 5 28656 5 28976 5 29296 5 29616 5 29936 5 30256 5 30576 6 30936 6 31320 6 31704 6 32088 6 32472 6 32856 6 33240 6 33624 6 34008 6 34392 6 34776 6 35160 6 35544 6 35928 6 36312 6 36696 7 36992 7 37440 7 37888 7 38336 7 38784 7 39232 7 39680 7 40128 7 40576 7 41024 7 41472 7 41920 7 42368 7 42816 8 43304 8 43816 8 44328 8 44840 8 45352 8 45864 8 46376 8 46888 8 47400 8 47912 8 48424 8 48936 9 49296 9 49872 9 50448 9 51024 9 51600 9 52176 9 52752 9 53328 9 53904 9 54480 9 55056 10 55416 10 56056 10 56696 10 57336 10 57976 10 58616 10 59256 10 59896 10 60536 10 61176 11 61664 11 62368 11 63072 11 63776 11 64480 11 65184 11 65888 11 66592 11 67296 12 68040 12 68808 12 69576 12 70344 12 71112 12 71880 12 72648 12 73416 13 73712 13 74544 13 75376 13 76208 13 77040 13 77872 13 78704 13 79536 14 80280 14 81176 14 82072 14 82968 14 83864 14 84760 14 85656 15 86016 15 86976 15 87936 15 88896 15 89856 15 90816 15 91776 16 92776 16 93800 16 94824 16 95848 16 96872 16 97896 17 98576 17 99664 17 100752 17 101840 17 102928 17 104016 18 104376 18 105528 18 106680 18 107832 18 108984 18 110136 19 110176 19 111392 19 112608 19 113824 19 115040 19 116256 20 117256 20 118536 20 119816 20 121096 20 122376 21 123120 21 124464 21 125808 21 127152 21 128496 22 130392 22 131800 22 133208 22 134616 23 134848 23 136320 23 137792 23 139264 23 140736 24 142248 24 143784 24 145320 24 146856 25 148176 25 149776 25 151376 25 152976

The method may further comprise: receiving information indicating a Modulation and Coding Scheme (MCS) and an available resource area size from a reception end; and determining the specific transport block size based on the received information from the predetermined transport block size combinations.

And, if the transport block size value based on the received information is not contained in the predetermined transport block size combinations, a maximum transport block size in the predetermined transport block size combinations, which is equal to or smaller than the transport block size value based on the received information; a minimum transport block size in the predetermined transport block size combinations, which is larger than the transport block size value based on the received information; or a specific transport block size in the predetermined transport block size combinations, which has a minimum difference with the transport block size value based on the received information, may be used as the specific transport block size.

In another aspect of the present invention, there is provided a signal transmission method comprising: attaching a first cyclic redundancy check (CRC) having a length of L to a transport block having a length of N; segmenting the transport block to which the first CRC is attached into M number of code blocks, each of which has a length of N_(c); attaching a second cyclic redundancy check (CRC) having a length of L to each of the M code blocks; encoding, by a turbo-encoder comprising an internal interleaver, the M code blocks, each of which has the second CRC; and transmitting the encoded M code blocks, wherein the transport block size N satisfies an equation denoted by N=M*N_(c)−L (where N, N_(c), M, and L are natural numbers), where a value of Nc+L has any one of block sizes of the internal interleaver of the turbo-encoder.

In another aspect of the present invention, there is provided a signal transmission method comprising: mapping a transport block having a length of N to at least one code block; encoding the at least one code block by a turbo-encoder comprising an internal interleaver; and transmitting the encoded code block, wherein the transport block size N is selected from a transport block size combination comprising all or some of values shown in a following table 3.

TABLE 3 16 24 32 40 48 56 64 72 80 88 96 104 112 120 128 136 144 152 160 168 176 184 192 200 208 216 224 232 240 248 256 264 272 280 288 296 304 312 320 328 336 344 352 360 368 376 384 392 400 408 416 424 432 440 448 456 464 472 480 488 504 520 536 552 568 584 600 616 632 648 664 680 696 712 728 744 760 776 792 808 824 840 856 872 888 904 920 936 952 968 984 1000 1032 1064 1096 1128 1160 1192 1224 1256 1288 1320 1352 1384 1416 1448 1480 1512 1544 1576 1608 1640 1672 1704 1736 1768 1800 1832 1864 1896 1928 1960 1992 2024 2088 2152 2216 2280 2344 2408 2472 2536 2600 2664 2728 2792 2856 2920 2984 3048 3112 3176 3240 3304 3368 3432 3496 3560 3624 3688 3752 3816 3880 3944 4008 4072 4136 4200 4264 4328 4392 4456 4520 4584 4648 4712 4776 4840 4904 4968 5032 5096 5160 5224 5288 5352 5416 5480 5544 5608 5672 5736 5800 5864 5928 5992 6056 6120 6200 6328 6456 6584 6712 6840 6968 7096 7224 7352 7480 7608 7736 7864 7992 8120 8248 8376 8504 8632 8760 8888 9016 9144 9272 9400 9528 9656 9784 9912 10040 10168 10296 10424 10552 10680 10808 10936 11064 11192 11320 11448 11576 11704 11832 11960 12088 12216 12384 12576 12768 12960 13152 13344 13536 13728 13920 14112 14304 14496 14688 14880 15072 15264 15456 15648 15840 16032 16224 16416 16608 16800 16992 17184 17376 17568 17760 17952 18144 18336 18568 18824 19080 19336 19592 19848 20104 20360 20616 20872 21128 21384 21640 21896 22152 22408 22664 22920 23176 23432 23688 23944 24200 24456 24496 24816 25136 25456 25776 26096 26416 26736 27056 27376 27696 28016 28336 28656 28976 29296 29616 29936 30256 30576 30936 31320 31704 32088 32472 32856 33240 33624 34008 34392 34776 35160 35544 35928 36312 36696 36992 37440 37888 38336 38784 39232 39680 40128 40576 41024 41472 41920 42368 42816 43304 43816 44328 44840 45352 45864 46376 46888 47400 47912 48424 48936 49296 49872 50448 51024 51600 52176 52752 53328 53904 54480 55056 55416 56056 56696 57336 57976 58616 59256 59896 60536 61176 61664 62368 63072 63776 64480 65184 65888 66592 67296 68040 68808 69576 70344 71112 71880 72648 73416 73712 74544 75376 76208 77040 77872 78704 79536 80280 81176 82072 82968 83864 84760 85656 86016 86976 87936 88896 89856 90816 91776 92776 93800 94824 95848 96872 97896 98576 99664 100752 101840 102928 104016 104376 105528 106680 107832 108984 110136 110176 111392 112608 113824 115040 116256 117256 118536 119816 121096 122376 123120 124464 125808 127152 128496 130392 131800 133208 134616 134848 136320 137792 139264 140736 142248 143784 145320 146856 148176 149776 151376 152976

where, the N value is a natural number.

According to the above-mentioned embodiments of the present invention, if a transport block received from an upper layer is segmented into a plurality of code blocks, and the code blocks are encoded by a turbo-encoder, the present invention is able to avoid addition of dummy bits due to the length of an input bit of an internal interleaver of the turbo-encoder, such that it can effectively transmit signals.

DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are included to provide a further understanding of the invention, illustrate embodiments of the invention and together with the description serve to explain the principle of the invention.

In the drawings:

FIG. 1 is a conceptual diagram illustrating basic operations of a turbo-encoder according to the present invention;

FIGS. 2 and 3 are conceptual diagrams illustrating a method for dividing a long transport block into a plurality of short transport blocks in a 3GPP system, and attaching a CRC to the short transport blocks according to the present invention;

FIG. 4 is a conceptual diagram illustrating a principle of establishing the transport block size according to one embodiment of the present invention; and

FIG. 5 shows an example of a resource structure according to the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts. Prior to describing the present invention, it should be noted that most terms disclosed in the present invention correspond to general terms well known in the art, but some terms have been selected by the applicant as necessary and will hereinafter be disclosed in the following description of the present invention. Therefore, it is preferable that the terms defined by the applicant be understood on the basis of their meanings in the present invention.

For the convenience of description and better understanding of the present invention, the following detailed description will disclose a variety of embodiments and modifications of the present invention. In some cases, in order to prevent ambiguous concepts of the present invention from occurring, conventional devices or apparatus well known to those skilled in the art will be omitted and be denoted in the form of a block diagram on the basis of the important functions of the present invention. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts.

As described above, it is well known to those skilled in the art that the internal interleaver of the turbo code has a superior performance in only a specific-sized data block. If the data block size is larger than a predetermined size, a transport block or a data block is segmented into a plurality of code blocks, and this process is called segmentation. Due to the limitation of the interleaver size, the transport or data block may not be segmented into the same-sized code blocks.

However, in the case of a downlink, a channel quality indicator must be applied to all code blocks segmented from the data block, such that it is preferable that the transport or data block be segmented into the same-sized code blocks. If the data block size or the segmented code block size is different from the internal interleaver size of the turbo code, a dummy bit is inserted such that transmission efficiency is reduced. In order to solve this problem, it is preferable that the segmentation process be performed not to require this dummy bit.

For the above-mentioned operations, there is needed a consideration of the block size of the internal encoder of the turbo-encoder caused by the inserted dummy bit. In order to perform the channel coding, a CRC is attached to a transport block or code blocks segmented from the transport block, and at the same time the length of each data block is changed to another length, such that a consideration of the channel coding is needed.

Firstly, the above-mentioned CRC attachment process will hereinafter be described in detail.

The CRC for detecting errors is attached to the transport block received from an upper layer. For the convenience of implementation, and it can also be attached to each of the segmented code blocks.

FIGS. 2 and 3 are conceptual diagrams illustrating a method for dividing a long transport block into a plurality of short length code blocks in a 3GPP system, and attaching a CRC to the short code blocks according to the present invention.

The 3GPP system segments a long transport block (TB) into a plurality of short code blocks, encodes the short code blocks, collects the encoded short code blocks, and transmits the collected short code blocks. Detailed descriptions of the above operations of the 3GPP system will hereinafter be described with reference to FIG. 2.

Referring to FIG. 2, the long transport block is CRC-attached, that is, a CRC is attached to the transport block at step S101. Thereafter, the CRC-attached long transport block is segmented into a plurality of short code blocks at step S102. Similar to this, as shown in reference numbers 201˜203 of FIG. 3, the CRC is attached to the long transport block, and the CRC-attached transport block is segmented into a plurality of code blocks. However, if the length of the transport block received from the upper layer is equal to or shorter than a predetermined length capable of being constructed by one code block, i.e., a maximum length of the internal interleaver of the turbo-encoder, the segmentation of the transport block may be omitted. In this case, the process for attaching a CB CRC may also be omitted.

In the meantime, each of short code blocks is CRC-attached, that is, the CRC attachment process is then performed on each of the code blocks at step S103. In more detail, as shown in the reference number 204 of FIG. 3, each of the code blocks includes a CRC.

Also, the code blocks, each of which includes the CRC, are applied to a channel encoder, such that the channel coding process is performed on the resultant code blocks at step S104. Thereafter, the rate matching process S105, and the code block concatenation and channel interleaving process S106 are sequentially applied to the individual code blocks, such that the resultant code blocks are transmitted to a reception end.

Therefore, according to the following embodiment, there is proposed a process for determining the size of a transport block in consideration of the two-stage CRC attachment process. In the case where the size of a transport block is less than a predetermined size (such as, maximum internal interleaver size) and this transport block is mapped to one code block, the embodiment of the present invention provides a method for establishing the transport block size in consideration of only one CRC.

Under the above-mentioned assumption, a method for mapping the transport block to one code block will hereinafter be described. In order to remove the necessity of the conventional art of attaching the dummy bit on the condition that the transport block is mapped to one codeword, this embodiment of the present invention allows the sum of the transport block size (N) and one CRC length to be equal to an block size of the internal interleaver of the turbo-interleaver. The following Table 1 represents a combination of block sizes of the internal interleaver of the turbo-encoder.

TABLE 1 i K 1 40 2 48 3 56 4 64 5 72 6 80 7 88 8 96 9 104 10 112 11 120 12 128 13 136 14 144 15 152 16 160 17 168 18 176 19 184 20 192 21 200 22 208 23 216 24 224 25 232 26 240 27 248 28 256 29 264 30 272 31 280 32 288 33 296 34 304 35 312 36 320 37 328 38 336 39 344 40 352 41 360 42 368 43 376 44 384 45 392 46 400 47 408 48 416 49 424 50 432 51 440 52 448 53 456 54 464 55 472 56 480 57 488 58 496 59 504 60 512 61 528 62 544 63 560 64 576 65 592 66 608 67 624 68 640 69 656 70 672 71 688 72 704 73 720 74 736 75 752 76 768 77 784 78 800 79 816 80 832 81 848 82 864 83 880 84 896 85 912 86 928 87 944 88 960 89 976 90 992 91 1008 92 1024 93 1056 94 1088 95 1120 96 1152 97 1184 98 1216 99 1248 100 1280 101 1312 102 1344 103 1376 104 1408 105 1440 106 1472 107 1504 108 1536 109 1568 110 1600 111 1632 112 1664 113 1696 114 1728 115 1760 116 1792 117 1824 118 1856 119 1888 120 1920 121 1952 122 1984 123 2016 124 2048 125 2112 126 2176 127 2240 128 2304 129 2368 130 2432 131 2496 132 2560 133 2624 134 2688 135 2752 136 2816 137 2880 138 2944 139 3008 140 3072 141 3136 142 3200 143 3264 144 3328 145 3392 146 3456 147 3520 148 3584 149 3648 150 3712 151 3776 152 3840 153 3904 154 3968 155 4032 156 4096 157 4160 158 4224 159 4288 160 4352 161 4416 162 4480 163 4544 164 4608 165 4672 166 4736 167 4800 168 4864 169 4928 170 4992 171 5056 172 5120 173 5184 174 5248 175 5312 176 5376 177 5440 178 5504 179 5568 180 5632 181 5696 182 5760 183 5824 184 5888 185 5952 186 6016 187 6080 188 6144

Therefore, as shown in Table 1, if the transport block is mapped to one code block, it is preferable that the transport block has a specific length acquired when the length of a CRC attached to the transport block is subtracted from an block size (K) of the internal interleaver. Provided that the length of a CRC attached to the transport block is 24 bits, the transport block size (N) acquired when the transport block is mapped to one code block may be a K-24. That is, the transport block size according to this embodiment may be selected from combinations of the following Table 4.

TABLE 4 i N 1 16 2 24 3 32 4 40 5 48 6 56 7 64 8 72 9 80 10 88 11 96 12 104 13 112 14 120 15 128 16 136 17 144 18 152 19 160 20 168 21 176 22 184 23 192 24 200 25 208 26 216 27 224 28 232 29 240 30 248 31 256 32 264 33 272 34 280 35 288 36 296 37 304 38 312 39 320 40 328 41 336 42 344 43 352 44 360 45 368 46 376 47 384 48 392 49 400 50 408 51 416 52 424 53 432 54 440 55 448 56 456 57 464 58 472 59 480 60 488 61 504 62 520 63 536 64 552 65 568 66 584 67 600 68 616 69 632 70 648 71 664 72 680 73 696 74 712 75 728 76 744 77 760 78 776 79 792 80 808 81 824 82 840 83 856 84 872 85 888 86 904 87 920 88 936 89 952 90 968 91 984 92 1000 93 1032 94 1064 95 1096 96 1128 97 1160 98 1192 99 1224 100 1256 101 1288 102 1320 103 1352 104 1384 105 1416 106 1448 107 1480 108 1512 109 1544 110 1576 111 1608 112 1640 113 1672 114 1704 115 1736 116 1768 117 1800 118 1832 119 1864 120 1896 121 1928 122 1960 123 1992 124 2024 125 2088 126 2152 127 2216 128 2280 129 2344 130 2408 131 2472 132 2536 133 2600 134 2664 135 2728 136 2792 137 2856 138 2920 139 2984 140 3048 141 3112 142 3176 143 3240 144 3304 145 3368 146 3432 147 3496 148 3560 149 3624 150 3688 151 3752 152 3816 153 3880 154 3944 155 4008 156 4072 157 4136 158 4200 159 4264 160 4328 161 4392 162 4456 163 4520 164 4584 165 4648 166 4712 167 4776 168 4840 169 4904 170 4968 171 5032 172 5096 173 5160 174 5224 175 5288 176 5352 177 5416 178 5480 179 5544 180 5608 181 5672 182 5736 183 5800 184 5864 185 5928 186 5992 187 6056 188 6120

In the meantime, a method for segmenting one transport block into two or more code blocks and performing a mapping process on the segmented code blocks will hereinafter be described in detail.

If one transport block is segmented into two or more code blocks, a CRC for the transport block is attached to the transport block as shown in FIGS. 2 and 3, and a CRC for each code block is attached to each of the segmented code blocks. Under this assumption, in order to avoid the conventional practice of adding of dummy bits, it is preferable that the sum of the size of a any one segmented code block and the size of a CRC attached to a corresponding code block is equal to an input bit size of the internal interleaver, as shown in Table 1.

Also, this embodiment of the present invention allows each of the segmented codewords to have the same size. Different-sized code blocks created by the segmentation of the transport block are caused by the limitation of the size of the internal interleaver of the turbo-encoder. If the transport block size is pre-established in consideration of the size of the internal interleaver of the turbo-encoder as described in this embodiment, there is no need for the individual code blocks to have different sizes.

Under the above-mentioned assumption, a method for establishing the size of the transport block according to this embodiment will hereinafter be described in detail.

FIG. 4 is a conceptual diagram illustrating a principle of establishing the transport block size according to one embodiment of the present invention.

Firstly, it is assumed that an L-sized CRC is attached to an N-sized transport block (TB). If the CRC-attached transport block (TB) size is longer than the maximum length of the internal interleaver, the transport block is segmented into a plurality of code blocks (CBs). As can be seen from FIG. 4, the transport block (TB) size is segmented into M (CB₁˜CB_(M)), each of which has the same length of N_(c) bits.

In the meantime, the L-sized CRC is attached to each of the M code blocks.

In this way, provided that each of the segmented code blocks has the same length and the lengths of two attached CRCs are considered, the transport block size N can be represented by the following equation 1:

N+L*M+L=M*(Nc+L)=>N=M*Nc−L  [Equation 1]

If the CRC of 24 bits is used, the above Equation 1 may be represented by another equation of N=M*Nc−24.

Each of the segmented code blocks includes the CRC, such that the CRC-attached code blocks are applied to the internal interleaver of the turbo-encoder. Therefore, as shown in FIG. 4, the length of the CRC-attached code blocks is equal to the internal interleaver's block size (K) shown in Table 1, as represented by the following equation 2:

Nc+L=K  [Equation 2]

Based on the above-mentioned description, this embodiment provides a method for using the following transport block sizes shown in the following Table 2. The following Table 2 shows a variety of cases illustrating a relationship between a single transport block and a maximum of 25 code blocks mapped to this single transport block.

TABLE 2 M N 2 6200 2 6328 2 6456 2 6584 2 6712 2 6840 2 6968 2 7096 2 7224 2 7352 2 7480 2 7608 2 7736 2 7864 2 7992 2 8120 2 8248 2 8376 2 8504 2 8632 2 8760 2 8888 2 9016 2 9144 2 9272 2 9400 2 9528 2 9656 2 9784 2 9912 2 10040 2 10168 2 10296 2 10424 2 10552 2 10680 2 10808 2 10936 2 11064 2 11192 2 11320 2 11448 2 11576 2 11704 2 11832 2 11960 2 12088 2 12216 3 12384 3 12576 3 12768 3 12960 3 13152 3 13344 3 13536 3 13728 3 13920 3 14112 3 14304 3 14496 3 14688 3 14880 3 15072 3 15264 3 15456 3 15648 3 15840 3 16032 3 16224 3 16416 3 16608 3 16800 3 16992 3 17184 3 17376 3 17568 3 17760 3 17952 3 18144 3 18336 4 18568 4 18824 4 19080 4 19336 4 19592 4 19848 4 20104 4 20360 4 20616 4 20872 4 21128 4 21384 4 21640 4 21896 4 22152 4 22408 4 22664 4 22920 4 23176 4 23432 4 23688 4 23944 4 24200 4 24456 5 24496 5 24816 5 25136 5 25456 5 25776 5 26096 5 26416 5 26736 5 27056 5 27376 5 27696 5 28016 5 28336 5 28656 5 28976 5 29296 5 29616 5 29936 5 30256 5 30576 6 30936 6 31320 6 31704 6 32088 6 32472 6 32856 6 33240 6 33624 6 34008 6 34392 6 34776 6 35160 6 35544 6 35928 6 36312 6 36696 7 36992 7 37440 7 37888 7 38336 7 38784 7 39232 7 39680 7 40128 7 40576 7 41024 7 41472 7 41920 7 42368 7 42816 8 43304 8 43816 8 44328 8 44840 8 45352 8 45864 8 46376 8 46888 8 47400 8 47912 8 48424 8 48936 9 49296 9 49872 9 50448 9 51024 9 51600 9 52176 9 52752 9 53328 9 53904 9 54480 9 55056 10 55416 10 56056 10 56696 10 57336 10 57976 10 58616 10 59256 10 59896 10 60536 10 61176 11 61664 11 62368 11 63072 11 63776 11 64480 11 65184 11 65888 11 66592 11 67296 12 68040 12 68808 12 69576 12 70344 12 71112 12 71880 12 72648 12 73416 13 73712 13 74544 13 75376 13 76208 13 77040 13 77872 13 78704 13 79536 14 80280 14 81176 14 82072 14 82968 14 83864 14 84760 14 85656 15 86016 15 86976 15 87936 15 88896 15 89856 15 90816 15 91776 16 92776 16 93800 16 94824 16 95848 16 96872 16 97896 17 98576 17 99664 17 100752 17 101840 17 102928 17 104016 18 104376 18 105528 18 106680 18 107832 18 108984 18 110136 19 110176 19 111392 19 112608 19 113824 19 115040 19 116256 20 117256 20 118536 20 119816 20 121096 20 122376 21 123120 21 124464 21 125808 21 127152 21 128496 22 130392 22 131800 22 133208 22 134616 23 134848 23 136320 23 137792 23 139264 23 140736 24 142248 24 143784 24 145320 24 146856 25 148176 25 149776 25 151376 25 152976

The Table 2 satisfies the above equations 1 and 2, and shows that up to the case when one transport block is segmented into 25 code blocks. Within the scope of satisfying the equations 1 and 2, those skilled in the art can easily appreciate an additional transport block (TB) size on the analogy of values shown in Table 2.

Since signal transmission is conducted by the above-mentioned embodiment of the present invention, the addition of dummy bit due to the limitation of the block size of the turbo-encoder can be removed, such that a system performance or throughput can be increased.

Meanwhile, in the case of considering not only a first case in which a transport block is mapped to one code block, but also a second case in which a transport block is segmented into two or more code blocks, the size of an available transport block can be represented by the following Table 3.

TABLE 3 16 24 32 40 48 56 64 72 80 88 96 104 112 120 128 136 144 152 160 168 176 184 192 200 208 216 224 232 240 248 256 264 272 280 288 296 304 312 320 328 336 344 352 360 368 376 384 392 400 408 416 424 432 440 448 456 464 472 480 488 504 520 536 552 568 584 600 616 632 648 664 680 696 712 728 744 760 776 792 808 824 840 856 872 888 904 920 936 952 968 984 1000 1032 1064 1096 1128 1160 1192 1224 1256 1288 1320 1352 1384 1416 1448 1480 1512 1544 1576 1608 1640 1672 1704 1736 1768 1800 1832 1864 1896 1928 1960 1992 2024 2088 2152 2216 2280 2344 2408 2472 2536 2600 2664 2728 2792 2856 2920 2984 3048 3112 3176 3240 3304 3368 3432 3496 3560 3624 3688 3752 3816 3880 3944 4008 4072 4136 4200 4264 4328 4392 4456 4520 4584 4648 4712 4776 4840 4904 4968 5032 5096 5160 5224 5288 5352 5416 5480 5544 5608 5672 5736 5800 5864 5928 5992 6056 6120 6200 6328 6456 6584 6712 6840 6968 7096 7224 7352 7480 7608 7736 7864 7992 8120 8248 8376 8504 8632 8760 8888 9016 9144 9272 9400 9528 9656 9784 9912 10040 10168 10296 10424 10552 10680 10808 10936 11064 11192 11320 11448 11576 11704 11832 11960 12088 12216 12384 12576 12768 12960 13152 13344 13536 13728 13920 14112 14304 14496 14688 14880 15072 15264 15456 15648 15840 16032 16224 16416 16608 16800 16992 17184 17376 17568 17760 17952 18144 18336 18568 18824 19080 19336 19592 19848 20104 20360 20616 20872 21128 21384 21640 21896 22152 22408 22664 22920 23176 23432 23688 23944 24200 24456 24496 24816 25136 25456 25776 26096 26416 26736 27056 27376 27696 28016 28336 28656 28976 29296 29616 29936 30256 30576 30936 31320 31704 32088 32472 32856 33240 33624 34008 34392 34776 35160 35544 35928 36312 36696 36992 37440 37888 38336 38784 39232 39680 40128 40576 41024 41472 41920 42368 42816 43304 43816 44328 44840 45352 45864 46376 46888 47400 47912 48424 48936 49296 49872 50448 51024 51600 52176 52752 53328 53904 54480 55056 55416 56056 56696 57336 57976 58616 59256 59896 60536 61176 61664 62368 63072 63776 64480 65184 65888 66592 67296 68040 68808 69576 70344 71112 71880 72648 73416 73712 74544 75376 76208 77040 77872 78704 79536 80280 81176 82072 82968 83864 84760 85656 86016 86976 87936 88896 89856 90816 91776 92776 93800 94824 95848 96872 97896 98576 99664 100752 101840 102928 104016 104376 105528 106680 107832 108984 110136 110176 111392 112608 113824 115040 116256 117256 118536 119816 121096 122376 123120 124464 125808 127152 128496 130392 131800 133208 134616 134848 136320 137792 139264 140736 142248 143784 145320 146856 148176 149776 151376 152976

When implementing the above described methodology, when a terminal identifies that the length of the CRC-attached transport block is larger than the largest interleaver block size, the terminal may determine the predetermined number of code blocks from a look-up table or may calculate the predetermined number of code blocks based upon a formula. The calculation may include calculating the predetermined number of code blocks based on the following equation:

C=┌B/(Z−L)┐, where

┌ ┐ represents a ceiling function,

C is the predetermined number of code blocks,

B is the length of the CRC-attached transport block,

Z is the largest interleaver block size, and

L is the first CRC length.

A signal transmission method and device according to this embodiment enables the transport block to have a predetermined length corresponding to any one of various values shown in Table 3. Table 3 shows the available transport block (TB) sizes which obviates the need for the conventional practice of inserting the dummy bit into the signal. The signal transmission method may allow sub-sets of Table 3 to be shared between a transmission end and a reception end in consideration of signaling overhead and the like, instead of using all the values of Table 36.

In the meantime, in order to inform the reception end of the transport block size, the transmission end is able to represent the transport block size by a combination of a modulation and coding scheme (MCS), and the size of allocated resources. By means of a channel quality indicator transferred from the reception end, a scheduler decides the MCS. The size of allocated resources is decided in consideration of not only resources for transferring control information but also other resources for a reference signal for channel estimation.

FIG. 5 shows an example of a resource structure according to the present invention.

Referring to FIG. 5, a horizontal axis indicates a time domain, and a vertical axis indicates a frequency domain. On the assumption that the resource structure of FIG. 5 is used, it is assumed that the resources for transferring control information correspond to 3 symbols and two transmission (Tx) antennas are used, one resource block (RB) includes 120 resource elements (REs) capable of being used to transmit data.

In this case, if it is assumed that the modulation rate is 64QAM, the coding rate is 0.6504, and the number of allocated resource blocks (RBs) is 10, the size of a data block capable of being transmitted is 4658 bits. These 4658 bits are located between 4608 bits and 4672 bits of Table 1. If it is assumed that the size of the transmittable data block is set to the 4608 bits or the 4672 bits, the data block size can be decided by various modulation and coding rates and the size of allocated resources.

As previously described in the above-mentioned example, if the size of an actually-transmittable data block is different from the size of a supportable data block, the size of the actually-transmittable data block can be decided by any of the following rules i)˜iii):

A method for deciding the actually-transmittable data block size as a maximally-supportable data block size which is equal to or smaller than the actually-transmittable data block size;

A method for deciding the actually-transmittable data block size as a minimally-supportable data block size larger than the actually-transmittable data block size; and

A method for deciding the actually-transmittable data block size as a supportable data block size which has a minimum difference with the actually-transmittable data block size.

In this case, if one transport block is transferred via one code block, the data block may correspond to the transport block. Otherwise, if one transport block is transferred via two or more code blocks, the data block may be considered to be the code blocks.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention. Thus, it is intended that the present invention cover the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents. For example, although the signal transmission method according to the present invention has been disclosed on the basis of the 3GPP LTE system, it can also be applied to other communication systems, each of which has a limitation in the block size during the encoding process and uses a combination of predetermined transport block sizes.

If a transport block received from an upper layer is segmented into a plurality of code blocks, and the code blocks are encoded by a turbo-encoder, the signal transmission method according to the present invention is able to remove the added dummy bits caused by a limitation of the block size of the internal interleaver of the turbo-encoder, such that it can effectively transmit signals. 

1. A method of performing, by a first device, channel coding for data to be transmitted to a second device, the method comprising: attaching a first CRC code to a transport block to produce a first CRC-attached transport block; segmenting the first CRC-attached transport block into multiple code blocks if a size of the first CRC-attached transport block is larger than a predetermined size; attaching a second CRC code to each of the multiple code blocks; and encoding the second CRC-attached code blocks by a turbo-encoder, wherein a size of the transport block is one of predetermined transport block sizes which comprises 6200, 6456, 6712, 6968, 7224, 7480, 7736, 7992, 8248, 8504, 8760, 9144, 9528, 9912, 10296, 10680, 11064, 11448, 11832, 12216, 12576, 12960, 13536, 14112, 14688, 15264, 15840, 16416, 16992, 17568, 18336, 19080, 19848, 20616, 21384, 22152, 22920, 23688, 24496, 25456, 26416, 27376, 28336, 29296, 30576, 31704, 32856, 34008, 35160, 36696, 37888, 39232, 40576, 42368, 43816, 45352, 46888, 51024, 52752, 57336, 59256, 61664, 63776, 66592, 68808, 71112,
 75376. 2. The method of claim 1, wherein the predetermined size is
 6144. 3. The method of claim 1, wherein a size of each of the first and second CRC codes is
 24. 4. The method of claim 1, wherein the predetermined size corresponds to a maximum block size of an internal interleaver within the turbo-encoder.
 5. A device of performing channel coding for data to be transmitted to a external device, the device configured to: attach a first CRC code to a transport block to produce a first CRC-attached transport block; segment the first CRC-attached transport block into multiple code blocks if a size of the first CRC-attached transport block is larger than a predetermined size; attach a second CRC code to each of the multiple code blocks; and encode the second CRC-attached code blocks by a turbo-encoder, wherein a size of the transport block is one of predetermined transport block sizes which comprises 6200, 6456, 6712, 6968, 7224, 7480, 7736, 7992, 8248, 8504, 8760, 9144, 9528, 9912, 10296, 10680, 11064, 11448, 11832, 12216, 12576, 12960, 13536, 14112, 14688, 15264, 15840, 16416, 16992, 17568, 18336, 19080, 19848, 20616, 21384, 22152, 22920, 23688, 24496, 25456, 26416, 27376, 28336, 29296, 30576, 31704, 32856, 34008, 35160, 36696, 37888, 39232, 40576, 42368, 43816, 45352, 46888, 51024, 52752, 57336, 59256, 61664, 63776, 66592, 68808, 71112,
 75376. 6. The device of claim 5, wherein the predetermined size is
 6144. 7. The device of claim 5, wherein a size of each of the first and second CRC codes is
 24. 8. The device of claim 5, wherein the predetermined size corresponds to a maximum block size of an internal interleaver within the turbo-encoder. 